The following invention relates to palletizers, and in particular, to a roller-assisted off-feed device for use thereon.
In U.S. Pat. No. 4,067,456 to Schmitt there is disclosed apparatus for arranging and stacking non-rigid articles, such as bags or the like. The apparatus disclosed therein includes a layer-arranging table, a stacking platform, and a roller carriage horizontally shiftable between a retracted position horizontally adjacent the layer-arranging table and an extended position overlying the stacking platform. The carriage surface is formed of a plurality of article-support rollers mounted for rotation about axes extending transversely of the path of travel of the carriage. The carriage serves to transfer a layer of articles from the layer-arranging table to the stacking platform, where the layers are stacked on a pallet. A fence vertically shiftable to an article-engaging position adjacent the stacking platform is operable to engage upstream edges of articles on the carriage, with the latter in its extended position. As the carriage is shifted from its extended to its retracted position, the fence retains the articles at a position above the stacking platform, wiping articles from the carriage onto the stacking platform.
From the above, it may be appreciated that the fence must exert a considerable force against the upstream edges of the articles in wiping articles from the roller carriage. This may produce two untoward effects. First, the articles to be palletized are commonly filled bags, such as bags of cement or the like, and these tend to be torn or otherwise damaged during the wiping operation. Second, bag articles are generally arranged on the carriage in upstream and downstream rows, so that the force of the fence is directed against the upstream row, and transmitted therefrom to the downstream row. In the wiping operation, the upstream row tends to be squeezed between the fence and the downstream row, disturbing the configuration of articles on the carriage as they are off-loaded.
One important object of the present invention is to provide an off-feed device, for use on the above-described type of bag palletizer, wherein the rollers of the carriage are caused to rotate in such direction to facilitate off-loading of articles from the carriage as the carriage is retracted and articles are transferred therefrom onto a stacking platform.
Yet another object of the invention is to provide such device which may be easily installed on existing palletizers of the above-described type, and which is easily operated.
The present invention in roller-assisted off-feed device is designed for use with the above-described palletizer and generally includes a vertically-shiftable contacting element overlying the stacking platform and extending horizontally in the direction of the path of travel of the palletizer roller carriage. With the carriage shifted to its extended position overlying the stacking platform, the contacting member is shifted from a raised to a lowered position wherein the element frictionally contacts the carriage rollers, preventing free rotation thereof. Shifting of the carriage toward its retracted position causes the rollers to rotate in a direction which advances articles in the direction opposite that of carriage movement, facilitating the off-loading of articles onto the stacking platform.
Other objects and features of the present invention will become more fully apparent from the following description of the invention and the accompanying drawings.